In this context the term “sobriety test” refers generally to a method for determining and testing the BAC of a subject; in particular it is not limited to determining and/or testing only low or zero BAC values or only ranges below a certain—e.g. legal—BAC limit.
There are several known methods for determining and testing the BAC of a subject. In practice, the BAC is measured in a blood sample of the subject or estimated from a breath alcohol content (BrAC). The latter method allows for quick and easy tests and is therefore wide-spread for different applications ranging from law enforcement to therapy monitoring and professional self-tests. BrAC may be measured using spectroscopy or with fuel cell sensors. The sensor arrangement may in principle comprise any of the known devices capable of determining the BrAC and/or BAC of a subject according to one of the above methods.
WO 2012/087187 A1 discloses a method and an apparatus for measuring BrAC based on a fuel cell sensor. The apparatus is a compact breathalyzer-type device, which displays the measured BrAC or a BAC estimated based on a BrAC measurement. As such, this apparatus is one possible embodiment of a sensor arrangement according to the definition used in the outset.
In case a device of the type disclosed in WO 2012/087187 A1 is used, testing the BAC comprises the steps of determining the BrAC from a breath sample provided by the subject, estimating a BAC from said BrAC, and determining whether the estimated BAC is within a predefined range. Said predefined range may be determined according to legal provisions or to corporate or personal guidelines.
Furthermore it has been suggested to indicate the test condition in a manner recognizable to the subject. In particular, a test device may indicate whether the device is inactive, a measurement or test is in progress, a test is confirmed or a test is non-confirmed. These test conditions may be visually and/or acoustically presented, e.g. on a display of the test device. In this context, the indication of the test condition, in particular of a confirmed test and the test result, can be recorded in order to authenticate the test result as well as the subject carrying out the test. However, it is evident that at least for visual indications, such recording of results and other data can be easily circumvented by subjects trying to avoid an unfavorable test outcome. For instance, a replica of the visual indication (a photo or the like) of an earlier legitimate test can be used to forge the process, while the test itself is carried out on a sample provided by a different, sober person.
A primary object of the present invention is to provide a process to eliminate or at least greatly reduce the risk of illegitimate tests, i.e. where the test result does not represent the condition of a subject being tested, as well as to provide a device for use in such a process.
In order to achieve the objective mentioned above, the present invention provides a process as defined in the outset, wherein said indication comprises a representation of a temporary validation code, meaning that the temporary validation code changes on a case-by-case basis with each individual test or measurement. The temporary validation code is unpredictable by the subject or user, in particular it does not follow any obvious regular pattern. The temporary validation code is generated or received prior to emission of said indication (s. below). Being a code, the temporary validation code is an arrangement of data or information without necessarily conveying any specific meaning or signification in itself other than being usable in connection with the present process. The indication may be any recordable message or signal, preferably one that is also in itself perceivable to a person who may subsequently verify the recorded indication. The representation of the temporary validation code is adapted to the type of indication (i.e. visual, audio-visual, electromagnetic, etc.). In particular the representation does not have to be reversible, i.e. it does not necessarily carry the full information of the temporary validation code. The representation may be a written expression of a part of the temporary validation code corresponding to a certain character encoding; or it may be a sequence of sounds corresponding to an acoustic encoding of (parts of) the temporary validation code.
By recording the indication comprising a representation of the temporary validation code together with a picture of the subject under test, the temporary validation code, confirming the execution of the test and the successful capturing of a test result, and the subject are associated in an un-reproducible manner. The emission and recording of (the representation of) the temporary validation code is simultaneous with the recording of the picture, thus creating an association between the temporary validation code (or its recorded representation) and the picture and thereby authenticating the picture. Preferably, both the capturing of the picture and the emission of the temporary validation code are performed immediately subsequent to the test, i.e. as soon as the test is finished and the test result is obtained. Therefore the picture shows the subject at the moment of the test result being captured or transmitted (or shortly thereafter; e.g. within a maximum latency of one second). The picture preferably shows the face of the subject while carrying out the test. In order to forge an authentic picture, a user would have to guess a valid temporary validation code in advance and provide a forged indication while doing and recording the test. It is therefore much harder, if at all possible, to forge the process.
The temporary validation code may also be used with other data captured during the confirmed test, such data may include but not limited to time-stamp, geo-location, latitude, atmospheric pressure, weather conditions.
Correspondingly, in order to achieve the objective mentioned above and with similar advantages, the present invention further provides a device as defined in the outset, wherein said controller is configured to operate said indicator to emit a representation of a temporary validation code when a notification of a confirmed test is provided by said sensor arrangement. The controller may comprise one or several components. The controller may be configured to receive a test result transmitted by said sensor arrangement or the controller may be part of the sensor arrangement, having access to the test result. The controller is further configured to generate or receive a temporary validation code. The indicator may be any device or arrangement capable of showing or otherwise communicating a representation of the temporary validation code as defined above. For instance it may be a display or speaker; it may also be a means for data transmission, allowing for electronic recording of (the representation of) the temporary validation code.
In a particularly advantageous embodiment, the sensor arrangement is integral with said device; more specifically, the sensor arrangement, the controller and the indicator may be integrated in one common unit or housing, thus providing a compact device for performing and authenticating sobriety tests.
Preferably the representation of the temporary validation code is a visual representation of the temporary validation code. Thus a visual representation of the temporary validation code is emitted as an indication of the confirmed test. Such temporary validation code may be visible to the test subject or may only be visible to those who have administrative rights to manage test results at the backend.
In this case the recorded picture of the subject may include an image of said visual representation according to the temporary validation code. A simple photograph, wherein the subject doing the test and the indication are in the same view field of a camera, suffices to authenticate the picture and the subject pictured thereon. The picture can be made with any smart computer device, such as a mobile phone, a car computer, an airplane computer or a factory access unit, comprising or being connected to a digital camera and the test may be recorded using a specialized app, preferably giving immediate feedback on the successful authentication. The visual representation of the temporary validation code can be a visual signal or a displayed message.
Correspondingly the indicator of the present device is preferably a visual indicator. In particular the indicator can be a display or light source, e.g. a light-emitting diode (LED). Besides the above-mentioned advantages of visual indications in connection with the authentication of the picture, such indicators are also relatively inexpensive and small and at the same time easy to handle and reliable compared to acoustic or electronic indicators.
Advantageously said visual representation is a color, wherein said indication is a flash of correspondingly colored light. The color may be selected from a set of predefined colors, the selection being based on the temporary validation code. Use of a color (e.g. red, green, blue, etc.) simplifies detection and verification of the representation within the picture. Also, emission of a flash of colored light, wherein the color of the flash light represents the temporary validation code, can be accomplished by a simple and inexpensive multicolor LED.
In order to associate the temporary validation code (i.e. the recorded representation thereof, which is comprised in the recorded indication) not only with a test instance but with a test result, the preset process may comprise the steps of emitting a representation of a test result of said test at the same time as said indication of the confirmed test, and recording said representation of the test result together with said indication and picture. Such an essentially simultaneous emission and recording of the test result and the temporary validation code creates a unique link between these two values. By this link or association, not only the sobriety test as such, but—more specifically—the test result can be authenticated.
If said indication comprises said representation of the test result, the emission and recording steps can be greatly simplified, because the same medium can be used for indication of the confirmed test as well as the test result. For instance, the emission of the representation of the temporary validation code can be preceded or succeeded by a similar indication of the test result. Or the temporary validation code itself contains an indication of the test result.
In another alternative, the process is characterized further by emitting said indication only when said BAC is within a predefined range, wherein said indication is an indication of a confirmed test with a test result signaling a sober subject or a subject at least having a BAC within said predefined range (i.e. an indication of a positive test result). In this instance, the emission of a temporary validation code already in itself, i.e. by its mere presence, expresses the finding of a positive test result corresponding to a sober subject. Because the test is a sobriety test, the term “positive” here refers to the sobriety of the subject. Since sobriety is defined as a BAC within the predefined range, whether or not the process and device described here (and with the above) are used to determine if the subject has a BAC between zero and a certain limit (or above that limit) is only and exclusively a question of the employed predefined range. On the other hand, if the subject is not sober, the sobriety test yields a negative test result.
In order to obtain an unpredictable temporary validation code the present process may comprise the step of generating said temporary validation code at random (e.g. using a random number generator) before emitting said indication and associating the generated temporary validation code with a test result. The test result can be recorded as such or through its representation in the recorded indication, in which latter case the generated temporary validation code would be associated with the recorded indication. In any case, the recorded representation of the temporary validation code is directly or indirectly (via the test result) associated with the generated temporary validation code and the picture of the subject. The authenticity of the picture can therefore be verified by comparing the recorded representation (recorded at the same time as the picture, as described above) with the associated validation code, e.g. by reproducing a similar representation from the associated validation code during verification. For instance when using a color representation, a color code may be associated with the picture and a corresponding color name (different representation) displayed next to the picture for verification of a recorded flash of colored light. Similar procedures may be applied e.g. to acoustic representations by comparing a recorded sound with a sound regenerated from an associated validation code.
In order to avoid the necessity of storing and transmitting the temporary validation code along with the picture and test result, which may be vulnerable to manipulation, the present process may instead comprise the step of deriving said temporary validation code from a time-stamp associated with a test result. The generation of the temporary validation code may follow a predefined algorithm, e.g. an encryption or the like, which is reproducible for verification of the validation code. During validation of a given picture and associated test result, the validation code may be first reproduced from a time-stamp of that picture and then the reproduced validation code is compared with the recorded representation. Naturally, the algorithm for deriving the validation code from the time stamp must remain secret. This may be achieved by implementing the algorithm in tamper-proof hardware or by similar measures.
For use-cases where professional self-tests are required, it is particularly useful to allow for central storage and verification of performed tests. In the present process this can be achieved by communicating with a remote database and transmitting a test result, the recorded indication (thus including the representation of said temporary validation code) and the recorded picture of said subject, as well as information associated with said test result where applicable (e.g. time-stamp and/or validation code), to said remote database. The test results provided by employees can thus be conveniently accessed and verified via said remote database. This is particularly useful where verification requires human interaction (e.g. for confirming the identity of a subject with the recorded picture and for comparing representations of validation codes), which can then be performed through a centralized procedure.
Additionally or alternatively the present process may comprise locally storing a test result, the recorded indication and the recorded picture of said subject, as well as information associated with said test result where applicable. In particular the protocol comprising the test results and any associated recorded information (at least a picture and a recording of the indication for each test result) can be stored locally in an encrypted format and optionally transmitted at a later time. This allows the application of the process even in offline applications, e.g. at workplaces underground.
The present device therefore preferably comprises a data transmission unit connected to said controller and configured to transmit a test result together with information allowing verification of said representation of the temporary validation code. For instance the temporary validation code may be transmitted as such or, when the code can be derived from a time-stamp, that time-stamp is transmitted. The data transmission unit may be a wireless transmission unit, e.g. a Bluetooth unit, for connection with a mobile phone or other digital devices of the subject under test.
To further improve the security of the test authentication or at least to provide information related to the circumstances of the performed tests, which may be useful to apply different guidelines to each test result according to the circumstances, the present process may comprise the step of associating additional test-related information with the test result, wherein said information comprises a blood alcohol content determined during the test, an assumed identity of the tested subject (i.e. the identity of a requested test subject), a geographic location of the test, a moment of test (i.e. date and time of the test), a latitude of the test (e.g. for on-flight tests), a hardware address of a test device (e.g. a MAC address of the test device) or a phone number of a communication device connected with said test device (e.g. a mobile phone or any other digital device used for establishing a connection between the test device and a remote database). The additional information may be used to confirm the validity of a recorded test, e.g. by comparing an associated hardware address with the hardware address of a personal test device of the subject and/or comparing an associated phone number with the personal phone number of the subject.
Specific authentication of test-related information can be achieved by assigning the temporary validation code to the additional test-related information. Said assigning may be achieved by associating the corresponding pieces of data, e.g. in a record or database, or by wrapping up or packaging the validation code together with the additional test-related information for storage or transmission. For example the validation code can be based on said additional information or derived therefrom or said additional information may be at least partly embedded in the temporary validation code.